The field of this invention relates generally to reserve battery cells and, more particularly, to an activation mechanism for a reserve battery cell.
Reserve battery cells are battery cells that can be maintained in an inactive state (i.e., a state in which power is neither generated nor stored) until power is needed for supplying to a load (e.g., a pump, a light bulb, or a computer). By maintaining reserve battery cells in the inactive state, the power generation and storage capacity characteristics of the battery cells are maximized. As a result, reserve battery cells have a substantially longer shelf life as compared to activated battery cells (i.e., a battery cell that is generating and/or storing power).
Reserve battery cells can generate and store power in a variety of different ways. For example, one particular reserve battery cell is an electrochemical, reserve battery cell in which an electrolytic solution is isolated from dry electrodes in the inactive state to facilitate preventing a power-generating chemical reaction between the electrolytic solution and the electrodes. To activate the electrochemical battery cell, the electrolytic solution is brought into contact with the electrodes thereby initiating the chemical reaction that generates power. At least some electrochemical, reserve battery cells utilize a partition or barrier that separates the electrolytic solution from the electrodes. When needed, a force can be applied to the partition to rupture or otherwise puncture the partition. In one known configuration, the external setback force that results from launching a projectile (e.g., an artillery shell) can be used to rupture the partition.
Reserve battery cells can power a variety of different devices in a variety of different environments, and an external force having a magnitude that is sufficient to be the sole activation force (i.e., sufficient to rupture the barrier between the electrolytic solution and the dry electrodes) may not be readily available when power output is desired. There is a need, therefore, for an activation mechanism that is operable when an external force is available but has a magnitude that is less than sufficient to be the sole activation force.